Temperature control for gas ranges



July 18, 1933. A. T. SCHMIDT TEMPERATURE CONTROL FOR GAS RANGES Filed Aug. 14, 1931' 3 Sheets-Sheet 1 IILH IE\LENTOR Wk M AM July 18, 1933. A SCHMlDT 1,918,872

TEMPERATURE CONTROL FOR GAS RANGES Filed Aug. 14, 1951 s Sheets-Sheet 2 July 18, 1933-. A. T. SCHMIDT TEMPERATURE CONTROL FOR GAS RANGES Filed Aug. 14, 1951 3 Sheets-Sheet 5 INVENTOR- ji ki Patented July 18, 1933' UNITED] STATES HOVERSON COMPANY, MILWAUKEE, VZ'ISCQNSIII,'A CORPORATION OF WISCONSIN:

rniurnnnrnnnoon'rnon ironens RANGES Application filed August 14 The present improvements relate, general, to gas ranges and more particularly to temperature regulating means forv gas range ovens, although they are also ofgeneral ap v plication and may be employed to control the 7 fuel supply to other burnersunder various conditions. I a

'A primary object of the improvements,

among others, is to provide a novel andefii cient heat regulator for ovens which is certain in operation, may be readilyset and can? be easily adjusted and calibrated.

A further object is to providev an improved temperature control having a simplified con struction which lends itself to a setting on the side or front of the range.

Other objects of the improvements will be apparent upon reference to the accompanying specification and drawings, inwhich Fig. 1 is a front elevation of a fragment of a gas range oven, showing one form of the improved temperature control, partly in section and elevation; I a V Fig. 2 is a side elevation of the oven illustrated in Fig. 1, showing theimprovements partly in section and partly iii-elevation, cer-- tain parts being omittedor broken away;

Fig. 3 is a rear elevationso-f a modified form, certain parts being in section Fig. 4: is a side elevation'of the, structure illustrated in Fig.v 3. 1

Referring to the drawings, only a fragment of the oven .5. of the range is'shown in Fig. 1. Conventional elements comprise the top 6, inner wall 7, outer side wall 8, fuel supply pipe 9 and oven burner 10," Inter-- ing screw 17 by-passesmai-n valve- 12, s o

that a small amount of fuel maybe supplied to burner 10, even thoughthe "supply is cut off by the closing 'ofvalve' 12'.-

A valve rod 18 is housed in tubing 19 which ,ieaig Serial No. 557,041.

extends from the valve 11 to bracket -20; This tubingnot only serves to protect the rod 18, but also maintains a definite distance between the valve 12 and the thermal. element. a valve rod extensionmember 21 which in turn is connected to valve '12. I

' A pin or rod 22 is loosely mounted in theupper end of bracket 2O,v in spaced relation to the upper end of rod'18. A heavy gauge thermostaticmetal strip v 23, bent into U- shape, is loosely'held in place between the pin. 22 and the upper end of rod 18, whereby The lower end of rod 18 engages ADOLPE T. .sonmrnrr, or MILWAUKEE, Wisconsin, nssronon ro LINDEMANN &

the latter is actuatedby the thermal element,

in response to risein temperature] As illustrated inv Fig. '1, the thermal element 23 and rod '18, are holding thevalve'l2 open, against the energy of a coil spring .24 which is pro ing direction.

" Meansfor adjusting the position of the thermal element and the parts movable therewith are provided in the pin operating lever 25 and screw 'in'e nber. 26 engaging same,

Saidlscrew is advanced or retracted by hand wheel 2'? which is secured in place by screw 28, while a temperature dial 29 is. clamped.

31 and isheld in any suchposition by the energy of spring 32 engaging collar 30. j d

ll hen the oven is cool and not in use,.th'e

trated in Fig.1. In this position, the thervided for, constantly urging the valve in clostemperature control is in the position 'illusmostatic member 23'is holding thelvalve 12 open, against the energy of spring 24.. Due to. thedial setting, vboth these members 23' and 25% are tensioned, sothat the energy of each is urging the valve in opposite ,dir'ec' tions: As illustrated, these opposed forces,

however, are balanced with the valve in openposition; When'either force preponderate's,

the valve is moved in a corresponding direction untll the forces become balanced again.

In use, the main valve-'33 controlling fuelto the oven (see F ig. 2) is opened "and the oven burner lighted.

Thed ial' may beset to any desired reading and. as the oven 5 heats up, the thermal element contracts,

, guished, whereupon the thermal member ex mains until again used.

causing the ends of the U-shaped member to come closer together, whereby the valve 12 is element-'23 has contracted sufficiently to per-' mit spring 24. to close valve 12. However, a minimum flame is maintained on burner 10, by having screw 17 open, thereby allowing sufficient fuel through the bypass 16, so that the burner never entirely goes out. A small flame is therefore present, when the valve 12 opens due to slight cooling of the oven below the temperature for which the'device'was set, so that the oven may be readily and immediately'heated up again to the proper temperature. owev'er, in case the flame is extin guished, the pilot light supplied with fuel through pipe 13, is continuouslyburning and v will rel ght the burner 10when-valve 12 opens'ag'ain after cooling of the oven. Balanifestly, any variation in'the temperature of the oven causes the position of the thermal member 23to change so'that the valve 12 will open or close to maintain the desired temperature inthe oven. When it is desired to discontinue use of the oven, the cock'33" may be closed and the burner extinpands on cooling and returns valve 12 to the open position illustrated in Fig; 1, where 1t re- In case thje actual temperature of the ovendoes notcoincidewith that indicated on the dial 29, the screw 28 may be loosened and he dial rotated until the correct reading is opposite the pointer 31, whence the screw may be fastened and the dial clamped tightly in place by wheel 27. The remaining tem-r peratures may then be calibrated on the dial, which will then be found'to be aecurate for use with the selected thermal element; Under conditions of use, the thermal element 23 may be placed under greater or less-tensionlDYlDZlHlPUlfitlIlg screw 26 through dial 29.

This causes lever 25 to move pin 22 whence the ends of member23 are brought closer together or moved away from each other, as the case may be. Such adjustments increase or diminish the movement, of the thermal ele- 'ment-in response to the heat, necessary to cause closing of the valve. 7

It will be understood that the parts 18 and 19 have been broken off for convenience in illustration so'as to condense the showmounted for use at the side of a range, the

modified form is adaptedifor use on the front thereof. Referring to the embodiment of Figs. 3 and4,the fuel supplyconduit 39 is provided with a valve'casing 41, having. a'

pilot burnerftube 43, a valve team a' by- 'passlb. Fueltothe pilot burner is controlledby screw 45, While'the by-pass is provided with adjustable screw 1-7. V The pro tecting tube {19, rods 48,51, bracket 50, thermal'element 53, and pin 52 are similar to the elements illustrated in the first embodiment.

Supported above the pin 52, is a lever 55'pivoted a; 56 which carries a lever 57, one end of which *engagespln 52 w th the other end engaging a pin 58'mounted in bracket 50. A

cam 59 engages pin 58 and has an operating lever 60 extendlng forwardly through the front wall 61 of the oven, where it terminates in a pointer 62. A dial housing 63 and dial 64: are provided on the front mu, the dial ing graduated with temperature readings. Upon reference'to'Fig. 3, one end of lever is engaged by adjusting screw 65, whichv rocks the lever about fulcrum 56, thereby elevatlng or lowering the fulcrum of lever 57.

The operation of this form" is similar to that earlier described. The lever 60 and pointer 62 are set to the desired temperature, the movement of which causes cam 59 to move thermal element 53 through pins 58 and 52 and lever 57. The mechanism thereafter functions to regulate the heat of the oven in the manner already described; In case the actual temperature does not coincide with that of the dial and pointer, an' adjustment may be made by moving adjusting screw '65 whereby the positionoflever 57 may be altered. In thismanner, the temperature 0011- trol may be] conveniently calibrated.

While the disclosed embodiments are preferable it is apparent that various element's' nay be modified For example, rods 18 21 may be provided inone piece, instead of being separate. "Various other modifications, within the scope-of the present-improvements, maybe made-without depart ing from the purview-of the invention.

'1'. The combination with an. oven burner, of a fuel supply-conduit therefor, a normally open valve in said conduit,"a rod operatively connected with said valve, an adjustable pin spaced from said rod',-'a* thermostatic element adapted to be tensioned ;'mounted on said rod open valve in said conduit, a rod operatively connected witn said valve, an adjustable pin spaced from said rod, a thermostatic element adapted to be tensioned; mounted 'onsaid rod and pin, a spring member urging said valve closed, an adjustable member engaging said pin, and a cam member for actuating said pin through said member for tensioning and untensioning said element;

open valve in said conduit, a rod operatively 7 connected with said valve, an adjustable pin spaced from said rod, a thermostaticelement adapted to be tensioned; mounted on said rod and pin, a spring member urging said valve closed, a second movable pin, an adjustable lever engaging both pins and a cam mem her for actuating said second pin whereby" said thermostatic element may be tensioned or untensioned. 5. A heat regulating devl-ce including an even, a burner therefor, a fuel supply pipe for said burner, a valve casing and disc valve disposed in said pipe for controlling the flow of fuel, a spring urging said valve closed, a bowed thermostatic element adapted to be tensioned for holding said valve open against the action of said spring in the cool position of said element, said element releasing its pressure againstsaid valve in'response to rise in temperature whereby said spring may be effective for closing same, the construction and arrangement being such, that the degree of opening'of said valve is inversely proportional to the degree of heat experienced, a movable pin upon which one end of said thermostatic element is support- .ed, and a movable indicator member for adj ustin g said pin and element. 7 a

6. A heat regulatmg device. compnsmg a burner, a fuelsupply pipe therefor, avalve casing in said pipe, a valve therein, said casing having a fuel port for conveying fuel to a pilot burner and a passage by-passing said valve, spring means urging-said valve in "closing direction and a U-shaped thermal element normally holding said valve open against the action of said spring, saidelement being adapted to be tensioned for hold ing said'valve' openagainst the action of said spring means. I a

7. A heat regulating devicev including a burner, a fuel supply pipe for said burner, a valve casing and a valve disposed in said pipe for controllingthe flow of fuel, a spring urging said valve closed, a rod-engaging said valve, a slidable pinlsubstantially aligned with said rod and spaced therefrom! a U- shaped thermal and spring element having its free ends engaging and supported by said rod and pin, a second movable pin spaced laterally of said first pin, a lever disposed between said pins and. engagingbotlnan eccentric engaging said second pin and a manually operable arm secured to said eccentric whereby movement of said eccentric'is trans mitted to said U-shaped element for tensioning same and concurrently opening said valve. I p

ADOLPH T. SCHMIDT.

CERTIFICATE OF CORRECTION.

Patent No. 1,918,872. July 18, 1933.

ADOLPH T. SCHMIDT.

It is hereby certified that the name of the assignee in the above numbered patent was erroneously described and specified as "Lindemann & Hoverson Company" whereas said name should have been described and specified as "A. J. Lindemann 8: Hoverson fiompany", as shown by the records of assignments in this office; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of August. A. I). 1933.

M. J. Moore.

(Seal) Acting Commissioner of Patents: 

